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History of Science Ancient Egypt

History of Science Online

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LibraryThing: Science in Ancient Mesopotamia Week 3: Ancient Egyptian and Aegean science

Anaximandros of Miletos (fl. 575 B.C.)

| Presocratics Index | Intro | Thales | Anaximandros | Anaximenes | Herakleitos | Parmenides | Zenon | Melissos |
| Atomists: Leukippos and Demokritos | Anaxagoras | Empedokles | Significance of the Presocratics |

Ancient science is sometimes a story of a handful of individuals, either isolated or connected by a tenuous relation, often communicating across a century or more in their writings rather than working together in a sustained collective enterprise or institution (as we know today). Yet Thales was followed by two successors in the same century in the same city of Miletos, both of whom advocated a variation of monism, the idea that everything can be reduced to a single principle. When Thales declared that water is the principle of all things, the significant implication of that declaration was that all things are made of one immortal divine principle, regardless of what that first principle might be. This commitment to monism became the legacy of Thales, continued and affirmed in his turn by Anaximandros (this page) and Anaximenes (next page).

Anaximandros of Miletos suggested that thunder is due not to Zeus, but to wind; similarly, lightning arises from the splitting of a cloud. Like Thales, Anaximandros of Miletos rejected the anthropomorphic Olympian gods in favor of an impersonal and monistic conception of divinity -- that everything is One. But unlike Thales, Anaximandros rejected water as the ultimate principle (archai) of all things.

That all things are made of water is not the kind of statement one is driven to by observation. Arguments then and now about what reality is and how it is best known are carried out on a high intellectual plane, and require a determined drive for rational order in the universe that flies in the face of normal observation -- this is especially the case for any assertion that everything is actually the same. Yet Anaximandros' answer seems even further removed from common experience and observation than water. Anaximandros reasoned that new things are continually coming to be from a boundless quantity of material, and these things have opposite qualities; e.g., some are wet and others dry. Yet if water were the principle of all things, then everything should be wet. Water and fire can destroy one another, so how could fire have come to be from only water? Rather, water must be considered as being itself one of the opposites; therefore it cannot be the primary thing (contra Thales). Thus the ultimate thing must be something as-yet-undifferentiated, without qualities, which could give rise to both wet-dry, hot-cold, and other opposite qualities in equal amounts and simultaneously. (Anaximandros might feel vindicated if he could hear a particle physicist today describe the creation of a pair of anti-particles from a fluctuation in an energy field!)

Aristotle, Physics. iii. 5 ; 204 b 22.
"But it is not possible that infinite matter is one and simple; either, as some say, that it is something different from the elements, from which they are generated, or that it is absolutely one. For there are some who make the infinite of this character, but they do not consider it to be air or water, in order that other things may not be blotted out by the infinite; for these are mutually antagonistic to one another, inasmuch as air is cold, water is moist, and fire hot; if one of these were infinite, the rest would be at once blotted out; but now they say that the infinite is something different from these things, namely, that from which they come." (Hanover Historical Texts Project)

For Anaximandros, that undifferentiated thing is apeiron, a Greek word derived from a Homeric adjective for without limit, without definition; the Boundless or indefinite. We will not translate it. For Anaximandros, apeiron is unlimited in quantity and extent, and has no physical characteristics such as wet or hot or dry or cold. Anaximandros regarded apeiron as divine, immortal, and indestructible; from it all things arise, all the heavens and the worlds within them.

Aristotle, Physics. iii. 4; 203 b 7.
"There is no beginning of the infinite [apeiron], for in that case it would have an end. But it is without beginning and indestructible, as being a sort of first principle; for it is necessary that whatever comes into existence should have an end, and there is a conclusion of all destruction. Wherefore as we say, there is no first principle of this [i.e. the apeiron], but it itself seems to be the first principle of all other things and to surround all and to direct all, as they say who think that there are no other causes besides the infinite (such as mind, or friendship), but that it itself is divine; for it is immortal and indestructible, as Anaximandros and most of the physicists say." (Hanover Historical Texts Project)

In contrast to the immortal divinity apeiron, all things produced from apeiron are transient: worlds, heavens, forms of life, elements with opposite qualities, all are continually coming to be or passing away. The transience of all qualities was associated with retributive justice, and the concept that reparation is due for encroachment. The emergence of one quality is an encroachment, or injustice imposed upon its opposite; for example, warmth encroaches in summer, then withdraws in winter. Thus each element must pay reparations for its encroachments, so that a lawful balance may be maintained. In this way human law was extended to the cosmos, in an eternal cycle of trespass and banishment in which all things participate.

To maintain Thales' monism in the face of the dualisms of common opposites, Anaximandros proposed the apeiron as a neutral thing that produces opposite qualities simultaneously. This is analogous to the diversification observed in natural growth, as when a homogenous seed develops into a plant with diverse parts such as roots, leaves, fruit, or bark.

Anaximandros was also credited with proposing a mechanism for how new worlds continually come to be by acquiring their forms in an eternally whirling vortex. The Earth is a cylindrical column surrounded by a fire. In the whirling vortex, heavy elements (such as earth and water) remain in the center, while lighter elements such as fire move outward to form gigantic rings around the Earth. Stars are punctured holes in the gigantic rings of fire, through which the fiery region beyond may be glimpsed from the Earth.

"The Sun and Moon are each an aperture in separate solid rings like the felloes of cartwheels. These rings consist of fire surrounded by air (regarded as concealing mist), and out of the single aperture in each of them fire emerges like air from the nozzle of a bellows.... Eclipses, and phases of the moon, are due to a total or partial blocking of the aperture.... The aperture of the Sun is the same size as the surface (presumably) of the Earth (fr. 129)....the diameter of its wheel is twenty-seven times as great as this (twenty-eight times in fr. 128). The Moon-wheel is nineteen Earth-diameters (or eighteen, presumably) across....The star-wheels ...were presumably of nine (or ten) earth-diameters, being nearest to the earth" (fr.127)." (Kirk & Raven, 146)

Anaximandros reportedly also believed that life evolved naturally from the sea -- humans, perhaps, from a fish such as the dog-shark (which has a placenta). Life evolved from the sea, Anaxamandros suggested, not from the actions of the Olympian gods, nor descended from the gods. Simple animals may spontaneously come into being.

Plutarch. Symp. viii. 730 E.
"Wherefore they (the Syrians) reverence the fish as of the same origin and the same family as man, holding a more reasonable philosophy than that of Anaximandros; for he declares, not that fishes and men were generated at the same time, but that at first men were generated in the form of fishes, and that growing up as sharks do till they were able to help themselves, they then came forth on the dry ground." (Hanover Historical Texts Project)

Without diminishing the striking interest of his views in cosmology and biology, Anaxamandros' affirmation of monism was the most fruitful tradition passed on to later presocratic philosophers.


First principle
Thales of Miletos
Anaximandros of Miletos


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HSCI 3013. History of Science to 17th centuryCreative Commons license
Kerry Magruder, Instructor, 2004
Brent Purkaple, TA

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Many thanks to the pedagogical model developed in Mythology and Folklore and other online courses by Laura Gibbs, which have been an inspiration for this course.

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